The invention relates to a method of wrapping smoking article rods with a wrapper, in particular in the production of cigars, to an apparatus for performing the method and to a smoking article comprising a wrapper applied by means of this method.
Conventional cigars include tobacco surrounded by an inner wrapper, which preferably is made of reconstituted tobacco. The inner wrapper is surrounded by an outer wrapper (in the following just wrapper), which usually comprises a section cut from natural tobacco leaf.
In the production of cigars, smoking article rods are prepared, which present the tobacco wrapped in the inner wrapper. Usually, one smoking article rod of this kind is used for more than one cigar, wherein the rod (after applying the wrapper, as described in the following) is cut into pieces to form individual cigars.
The standard type of cigar wrapping machine based on the “bobbin system” includes a conveyer provided with a bobbin unwinder and a rewinder. A bobbin processed in this machine comprises a wound web and individual spaced wrappers (usually sections of natural tobacco leaf, as mentioned above), which have a longitudinal axis each and are arranged side by side on the web. That means, the longitudinal axes of the wrappers are generally running transversely (not necessarily orthogonally) with respect to the longitudinal direction of the web, and they are arranged in a spaced manner and more or less in parallel with respect to each other. When the web is wound, the wrappers stick between adjacent layers of the web such that they keep their positions.
In use of the machine, the bobbin is unwound, and an unwound section of the web is guided across a support, wherein the wrappers on that section of the web are exposed. Now each wrapper is picked up by means of a needle of a transfer device which passes the wrapper from the web to a rolling station. In the rolling station, the wrapper is helically wound, using three rollers, about an essentially fixed smoking article rod of the type described above, which has been moved before to the rolling station by a conveyer. The empty web passes to the rewinder where it is wound to form an empty bobbin.
The transfer device moves back and forth between the position where it picks up a wrapper from the unwound web and the rolling station where the wrapper is applied to the smoking article rod. Since the transfer device includes a relatively heavy arm, the production speed is limited due to the inertia and the reciprocating movement of this arm. Typically, about 80 smoking article rods per minute can be wrapped in this way, which corresponds to about 160 cigars per minute when one wrapped smoking article rod is cut into two cigars afterwards.